
<template>
  <span :endTime="endTime" :endText="endText">
    <slot>{{ content }}</slot>
  </span>
</template>

<script>
export default {
  data() {
    return {
      content: '',
    }
  },
  props: {//接收父组件的数据
    endTime: { type: String, default: '' },
    endText: { type: String, default: '活动已结束' },
  },
  watch: {//监听时间的变化
    endTime() {
      this.countdowm(this.endTime)
    }
  },
  mounted() {
    this.countdowm(this.endTime)
  },
  methods: {
    countdowm(timestamp) {
      let self = this;
      let timer = setInterval(function () {
        let nowTime = new Date();
        let endTime = new Date(timestamp * 1000);
        let t = endTime.getTime() - nowTime.getTime();
        if (t > 0) {
          let day = Math.floor(t / 86400000);
          let hour = Math.floor((t / 3600000) % 24);
          let min = Math.floor((t / 60000) % 60);
          let sec = Math.floor((t / 1000) % 60);
          hour = hour < 10 ? "0" + hour : hour;
          min = min < 10 ? "0" + min : min;
          sec = sec < 10 ? "0" + sec : sec;
          let format = '';
          if (day > 0) {
            format = `${day}天${hour}小时${min}分${sec}秒`;
          }
          if (day <= 0 && hour > 0) {
            format = `${hour}小时${min}分${sec}秒`;
          }
          if (day <= 0 && hour <= 0) {
            format = `${min}分${sec}秒`;
          }
          self.content = format;
        } else {
          clearInterval(timer);
          self.content = self.endText;
        }
      }, 1000);
    }
  }
}
</script>
